add a job for migrating broker storage versions to v1beta1

[vaikas]

Fixes #3261

Proposed Changes

• Add a Preinstall job that migrates Brokers from v1alpha1 to v1beta1.

Release Note

- 🗑️ Remove feature or internal logic
Eventing v1alpha1 API is removed.
action required: You must run pre-install job prior to upgrading to get Brokers to v1beta1 API.

Docs
knative/docs#2543

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[matzew]

what's the difference between "preinstall" and upgrade ?

just wondering, since we have post-install, and upgrade already. and now pre-install ?

Just wondering

[vaikas]

I think upgrade might have been a poor name. I think it's cleaner to indicate which steps need to happen before upgrade (preinstall) and which have to happen after (postinstall). Anyways, that was my thinking :)

[vaikas]

perhaps preupgrade / postupgrade is better? :) Since you don't need to run those if you're doing a fresh install. Serving called it post install, so went with that last time.

[matzew]

no, I like

pre-install
post-install

I just did not really like upgrade :-)

[lionelvillard]

/lgtm

[vaikas]

/test pull-knative-eventing-upgrade-tests

[vaikas]

/test pull-knative-eventing-integration-tests